Prof Piercy, who joined as dean from the University of Warwick last summer, said the school had since written to Prof Bladen-Hovell’s vice-chancellor to complain about his conduct.

It follows the publication on Swansea University’s intranet of a report by Prof Bladen-Hovell in which he said a decision by the School of Management to “systematically re-scale marks” was taken despite the “serious concern” of external examiners.

Prof Bladen-Hovell said apparent grade inflation “seriously debases the standard” of the university’s economics degree and the subsequent risk of reputational damage to Swansea was “very large indeed”.

He added: “If I were a cynic, I might be tempted to conclude that the adjustment of marks is a blatant attempt by the management team to increase league table performance by manipulation of degree outcomes.”

But in e-mails sent to staff and leaked to the Times Higher Education (THE) trade magazine earlier this month Prof Piercy defended his decision to re-scale final year economics marks.

He said re-scaling was a “completely acceptable practice” that was “widely used” elsewhere and appeared to criticise some of his own department for doubting his methods. He added: “As a result of the political behaviour of colleagues to attack a legitimate evaluation process in pursuit of their own ends our students are paying the price.”

In a broadside at Prof Bladen-Hovell, Prof Piercy said the external examiner had “not published since 2004” and his behaviour during his time at Swansea “was such that we have written a letter of complaint to his [vice-chancellor]. Using profane language and aggression towards our staff is not acceptable.”

Responding, Prof Bladen-Hovell told THE that the comments “appear [to be] an attempt to shore up [Prof Piercy’s] own position by attacking my professional integrity and credibility. [They] reflect very poorly on him and the allegations about my behaviour do not match my recollection of events.” He said Swansea’s registrar, Raymond Ciborowski, had “agreed to pursue the matter”.

Earlier this month the School of Management reported a 6% drop in overall satisfaction for its economics programmes in the National Student Survey (NSS). It said the “disappointing result” was “perhaps a legacy of the outdated modules and approaches in the now-closed parts of the school”.

A spokesman for Swansea University said: “The matters raised in the report... had already been identified by our internal quality processes, which concerned an issue with the processing of undergraduate assessment marks in one area of the university. Decisive action was taken at an early stage to rectify that issue, prior to the receipt of the external examiner’s full report, and a report on the action has been submitted to the university’s academic committees and external examiners.

“Our external examiners and students can have absolute confidence in the university’s assessment systems, quality assurance processes and the standards of all our degrees and awards and we greatly value the important contribution which our external examiners make in these respects.”

Keele University failed to respond to a request for a comment on the issue.